Method, apparatus, and product for leasing of group membership in a distributed system

• US 6,925,644 B2
• Filed: 01/31/2003
• Issued: 08/02/2005
• Est. Priority Date: 10/11/1996
• Status: Expired due to Fees

• Current Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Scheifler, Robert, Waldo, James H., Wollrath, Ann M., Arnold, Kenneth C. R. C.
• Primary Examiner(s): Courtenay, III, St. John
• Assistant Examiner(s): Nguyen, Van H.
• Application Number:
  US10/355,217
• Publication Number:
  US 20030115374A1
• Time in Patent Office: 914 Days
• Field of Search: 718/104, 719/316, 707/206, 707/10, 707/201, 707/205
• US Class Current: 718/104
• CPC Class Codes: G06F 12/0253 Garbage collection, i.e. reclamation of unreferenced memory
• CPC Class Codes: G06F 12/0261 using reference counting
• CPC Class Codes: G06F 16/289 Object oriented databases
• CPC Class Codes: G06F 9/4411 Configuring for operating with peripheral devices; Loading of device drivers
• CPC Class Codes: G06F 9/465 Distributed object oriented systems remote method invocation [RMI] G06F9/548
• CPC Class Codes: G06F 9/5011 the resources being hardware resources other than CPUs, Servers and Terminals
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: G06F 9/547 Remote procedure calls [RPC]; Web services
• CPC Class Codes: H04L 12/417 with deterministic access, e.g. token passing
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99957 Garbage collection

Abstract

A system for leasing a group membership in a distributed processing system is provided. In accordance with this system, a remote object requests from an activation group a membership in the activation group for a period of time. Responsive to this request, the activation group determines an appropriate lease period during which time the remote object becomes a member of the activation group and runs in the same address space as other objects of the activation group.

Claims

1. A method, comprising:

providing, to an object manager, a lease request for accessing a resource for a lease period;

receiving, from the object manager, a lease object for managing the lease; and

accessing the resource following receipt of the lease object.

2. The method of claim 1, wherein managing the lease comprises:

invoking a renew method associated with the lease object; and

accessing the resource for an extended lease period based on the invocation.

3. The method of claim 1, wherein managing the lease comprises:

invoking a cancel method associated with the lease object; and

terminating access to the resource based on the invocation.

4. The method of claim 1, wherein receiving, from the object manager, a lease object for managing the lease further comprises:

notifying an object collector in response to receiving the lease object.

5. The method of claim 4, wherein notifying the object collector comprises:

providing a copy of the lease object to the object collector.

6. A lease management method comprising:

receiving, from a client, a request to invoke a method on an object associated with a set of objects;

determining whether a lease granted to the object expired; and

invoking the method based on the determination.

7. The method of claim 6, wherein invoking the method based on the determination comprises:

associating the object with a new set of objects based on a determination that the lease expired.

8. The method of claim 7, wherein placing the object in a new set of objects further comprises:

loading the object into an address space associated with a computing device that corresponds to the new set of objects.

9. The method of claim 6, wherein invoking the method based on the determination comprises:

determining whether the set of objects is running in a virtual machine; and

loading the object into an address space associated with the virtual machine.

10. The method of claim 9, wherein loading the object comprises:

starting a virtual machine for the set of objects based on the determination that the set of objects is not running in a virtual machine.

11. The method of claim 6, wherein determining whether a lease granted to the object expired comprises:

determining whether a lease granted to the object expired based on a lease object provided by the object.

12. The method of claim 11, wherein the lease object includes a method for determining a lease period associated with the lease.

13. A lease management method performed by an object manager, comprising:

receiving a request for a lease for accessing a resource associated with a set of objects corresponding to the object manager;

validating the lease request; and

providing an object based on a result of the validation.

14. The method of claim 13, wherein validating the lease request comprises:

determining whether the lease request includes an exact lease request.

15. The method of claim 14, wherein providing an object comprises:

providing an exception object based on a determination that the exact lease request includes an unacceptable requested lease period.

16. The method of claim 14, wherein providing an object comprises:

providing a lease object based on a determination that the exact lease request includes an acceptable requested lease period.

17. The method of claim 13, wherein providing an object comprises:

providing a lease object based on the determination that the lease request is proper.

18. The method of claim 17, wherein the lease object includes methods for managing the lease.

19. The method of claim 17, wherein the lease object may be used by at least one of an object that provided the lease request and an object collector.

20. The method of claim 13, wherein providing an object comprises:

providing either an exception object or a lease object based on the determination.

21. A computer-readable medium including instructions for performing a method, when executed by a processor, the method comprising:

providing, to an object manager, a lease request for accessing a resource for a lease period;

receiving, from the object manager, a lease object for managing the lease; and

accessing the resource following receipt of the lease object.

22. The computer-readable medium of claim 21, wherein managing the lease comprises:

invoking a renew method associated with the lease object; and

accessing the resource for an extended lease period based on the invocation.

24. The computer-readable medium of claim 21, wherein receiving, from the object manager, a lease object for managing the lease further comprises:

notifying an object collector in response to receiving the lease object.

25. The computer-readable medium of claim 24, wherein notifying the object collector comprises:

providing a copy of the lease object to the object collector.

23. The computer-readable medium of wherein managing the lease comprises:

invoking a cancel method associated with the lease object; and

terminating access to the resource based on the invocation.

26. A computer-readable medium including instructions for performing a method, when executed by an object collector, the method comprising:

receiving, from a client, a request to invoke a method on an object associated with a set of objects;

determining whether a lease granted to the object expired; and

invoking the method based on the determination.

27. The computer-readable medium of claim 26, wherein invoking the method based on the determination comprises:

associating the object with a new set of objects based on a determination that the lease expired.

28. The computer-readable medium of claim 27, wherein placing the object in a new set of objects further comprises:

loading the object into an address space associated with a computing device that corresponds to the new set of objects.

29. The computer-readable medium of claim 26, wherein invoking the method based on the determination comprises:

determining whether the set of objects is running in a virtual machine; and

loading the object into an address space associated with the virtual machine.

30. The computer-readable medium of claim 29, wherein loading the object comprises:

starting a virtual machine for the set of objects based on the determination that the set of objects is not running in a virtual machine.

31. The computer-readable medium of claim 26, wherein determining whether a lease granted to the object expired comprises:

determining whether a lease granted to the object expired based on a lease object provided by the object.

32. The computer-readable medium of claim 31, wherein the lease object includes a method for determining a lease period associated with the lease.

33. A computer-readable medium including instructions for performing a method, when executed by an object manager, the method comprising:

receiving a request for a lease for accessing a resource associated with a set of objects corresponding to the object manager;

validating the lease request; and

providing an object based on a result of the validation.

34. The computer-readable medium of claim 33, wherein validating the lease request comprises:

determining whether the lease request includes an exact lease request.

35. The computer-readable medium of claim 34, wherein providing an object comprises:

providing an exception object based on a determination that the exact lease request includes an unacceptable requested lease period.

36. The computer-readable medium of claim 34, wherein providing an object comprises:

providing a lease object based on a determination that the exact lease request includes an acceptable requested lease period.

37. The computer-readable medium of claim 33, wherein providing an object comprises:

providing a lease object based on the determination that the lease request is proper.

38. The computer-readable medium of claim 37, wherein the lease object includes methods for managing the lease.

39. The computer-readable medium of claim 37, wherein the lease object may be used by at least one of an object that provided the lease request and an object collector.

40. The computer-readable medium of claim 33, wherein providing an object comprises:

providing either an exception object or a lease object based on the determination.

41. A system, comprising:

means for providing, to an object manager, a request for a lease for accessing a resource for a lease period;

means for receiving, from the object manager, a lease object for managing the lease; and

means for accessing the resource in response to receiving the lease object.

42. The system of claim 41, wherein the means for managing the lease comprises:

means for invoking a renew method included in the lease object; and

means for accessing the resource for an extended lease period based on the invocation.

43. The system of claim 41, wherein the means for managing the lease comprises:

means for invoking a cancel method included in the lease object; and

means for terminating access to the resource based on the invocation.

44. The system of claim 41, wherein the means for receiving, from the object manager, a lease object for managing the lease further comprises:

means for notifying an object collector in response to receiving the lease object.

45. The system of claim 44, wherein the means for notifying the object collector comprises:

means for providing a copy of the lease object to the object collector.

46. An object collector, comprising:

means for receiving, from a client, a request to invoke a method on an object associated with a set of objects;

means for determining whether a lease granted to the object expired; and

means for invoking the method based on the determination.

47. The system of claim 46, wherein the means for invoking the method based on the determination comprises:

means for associating the object with a new set of objects based on the determination that the lease expired.

48. The system of claim 47, wherein the means for placing the object in a new set of objects further comprises:

means for loading the object into an address space associated with a virtual machine that corresponds to the new set of objects.

49. The system of claim 46, wherein the means for invoking the method based on the determination comprises:

means for determining whether the set of objects is running in a virtual machine; and

means for loading the object into an address space associated with the virtual machine.

50. The system of claim 49, wherein the means for loading the object comprises:

means for starting a virtual machine for the set of objects based on the determination that the set of objects is not running in a virtual machine.

51. The system of claim 46, wherein the means for determining whether a lease granted to the object expired comprises:

means for determining whether a lease granted to the object expired based on a lease object provided by the object.

52. The system of claim 51, wherein the lease object includes a method for determining a lease period associated with the lease.

53. An object manager, comprising:

means for receiving a request for a lease for accessing a resource associated with a set of objects corresponding to the object manager;

means for determining whether the lease request is proper; and

means for providing an object based on the determination.

54. The system of claim 53, wherein the means for determining whether the lease request is proper comprises:

means for determining whether the lease request includes an exact lease request.

55. The system of claim 54, wherein the means for providing an object comprises:

means for providing an exception object based on a determination that the exact lease request includes an unacceptable requested lease period.

56. The system of claim 54, wherein the means for providing an object comprises:

means for providing a lease object based on a determination that the exact lease request includes an acceptable requested lease period.

57. The system of claim 53, wherein the means for providing an object comprises:

means for providing a lease object based on the determination that the lease request is proper.

58. The system of claim 57, wherein the lease object includes methods for managing the lease.

59. The system of claim 57, wherein the lease object may be used by at least one of an object that provided the lease request and an object collector.

60. The system of claim 53, wherein the means for providing an object comprises:

means for providing either an exception object or a lease object based on the determination.

61. A system, comprising:

a client for providing a request for invoking a method; and

a server for invoking the method on an object based on the request, the server including;

a first process for activating the object based on a relationship between the object and a set of objects, and

a second process associated with the set of objects for managing one or more leases corresponding to the set of objects.

62. The system of claim 61, wherein the first process activates the object when the relationship reflects that the object is a member of the set of objects.

63. The system of claim 61, wherein the first process places the object in a new set of objects when the relationship reflects that the object is not a member of a set of objects.

64. The system of claim 61, wherein the first process activates the object when the relationship reflects that the object holds a lease with the set of objects.

65. The system of claim 61, wherein the first process places the object in a new set of objects when the relationship reflects that the object does not hold a lease with the set of objects.

66. The system of claim 61, wherein the second process provides a lease object in response to a request for a lease with the set of objects.

67. The system of claim 66, wherein the request for the lease is received from the object.

68. The system of claim 66, wherein the lease object includes an indication of a lease period during which the object may utilize address space associated with the set of objects.

69. The system of claim 61, wherein a lease object is used to renew a lease corresponding to the set of objects.

70. The system of claim 69, wherein the object renews the lease based on a determination that the lease is about to expire.

71. The system of claim 69, wherein the lease object is used to determine that the lease is about to expire.

72. The system of claim 61, wherein the object notifies the first process when the second process grants a lease corresponding to the set of objects to the object.

73. The system of claim 61, wherein the server further includes a plurality of second processes, each corresponding to a respective set of objects.

74. The system of claim 61, wherein each second process may grant a lease corresponding to their respective set of objects to the object.